JPH05190139A - Electric discharge lamp - Google Patents

Abstract

PURPOSE:To improve the reduction of light quantity immediately after the put ON and simplify a manufacturing process without using an auxiliary amalgam. CONSTITUTION:The inner wall of a bulb 1 having an opening at one edge is coated with a fluorescent material 2, and the opening edge is sealed by a stem 3. A supporting body 5 made of the material whose shape is changed by the temperature change, e.g. bimetal is fitted on a supporting tube 4 installed at the stem 3, and an amalgam metal 7 is installed through a supporting wire 6 at the top edge. The supporting body 5 is made straight when the lamp is put OFF state, and holds the amalgam metal 7 at the position close to the center of the bulb 1, while if the lamp is in put ON state, the supporting body 5 is bent by the temperature rise, and holds the amalgam metal 7 at the low temperature part in the bulb 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp that discharges and emits mercury vapor enclosed in a bulb.

[0002]

2. Description of the Related Art In a discharge lamp containing mercury,
It is important to control the mercury vapor pressure, and when the temperature of the discharge lamp becomes high, the mercury vapor pressure rises excessively, exceeds the optimum vapor pressure, and the efficiency decreases.

As a solution to this problem, there is a method using amalgam metal. The amalgam temperature of the amalgam that achieves the optimum mercury vapor pressure can be controlled by the mixing ratio of the metal and mercury used.

However, since amalgam has an optimum vapor pressure when the lamp becomes hot, when the lamp is cold, for example, when the lamp is started, the vapor pressure is considerably low and the lamp is dark. Therefore, there is a method of arranging another amalgam (auxiliary amalgam) in a portion where the temperature becomes high immediately after the lamp is turned on, in order to improve the decrease in the amount of light immediately after the lamp is turned on.

When the amalgam is sealed in the lamp, the amalgam metal is put in the bulb in advance, the stem and the bulb are sealed, heated and evacuated, and sealed. After that, the amalgam metal was moved to a predetermined position inside the valve, and was externally heated to be melted and fixed to the inner wall of the valve.

[0006]

By the way, when two amalgams are used as described above, when the lamp is turned on and the lamp is in a steady state, the auxiliary amalgam hardly holds mercury. , Therefore, it is not involved in the control of mercury vapor pressure in the lamp.

That is, the auxiliary amalgam is unnecessary in a steady state after the lamp is turned on, but it must be attached in order to improve the decrease in the light amount at the start, and the process becomes complicated.

Further, the amalgam is fixed to a place where the stem is sealed in the case of a single-ended lamp, and when the stem and the bulb are sealed, the amalgam is located in another low temperature place in the lamp. Therefore, it is necessary to return it to a predetermined position after exhaust gas sealing, which complicates the process.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a discharge lamp capable of improving a decrease in light amount immediately after lighting and not requiring an auxiliary amalgam.

[0010]

In order to solve the above problems, the present invention relates to a discharge lamp in which at least mercury is enclosed in a translucent bulb and an amalgam metal for controlling the mercury vapor pressure thereof is enclosed. In, while arranging the amalgam metal via a support whose shape is changed by temperature change, the shape change of the support, when the lamp is off, the amalgam metal is arranged at substantially the center of the bulb,
It is characterized in that it is arranged at a low temperature portion inside the bulb when it is turned on.

[0011]

With the above-described structure, the amalgam is placed substantially in the center of the bulb immediately after the lamp is turned on, and the temperature of the center of the bulb becomes high immediately after the lamp is turned on. Therefore, no conventional auxiliary amalgam is required. Further, when sealing the stem and the valve, since the amalgam is placed in the approximate center of the valve, the amalgam does not get in the way and after exhaust sealing, the step of returning to a predetermined position is unnecessary, Is simplified.

[0012]

Embodiment 1 FIG. 1 shows an embodiment of the present invention, in which the lamp is an electrodeless discharge lamp. In the figure, reference numeral 1 is a bulb-shaped bulb having one end opening, a fluorescent body 2 is applied to the inner wall of the bulb, and a glass stem 3 is sealed to the opening end. 4 is a support tube provided in advance on the stem 3,
A support 5 made of a material whose shape is changed by temperature change, for example, a bimetal is inserted into the support tube 4, and an amalgam metal 7 is attached to a tip end of the support 5 via a support wire 6. In this case, the amalgam metal 7 is held by dissolving the amalgam metal 7 in a metal that is familiar to the amalgam metal 7, for example, a nickel mesh 8.

Here, the support 5 is straight as shown in FIG. 1 (a) when the lamp is off, and holds the amalgam metal 7 at a position close to the center of the bulb 1. As the temperature rises while the lamp is on,
It is designed to bend and hold the amalgam metal 7 at a low temperature portion in the valve 1 as shown in (b).

With this structure, the amalgam temperature rises rapidly at the start of the lamp, and the rising characteristics of the luminous flux at the start can be improved. Further, after lighting, the support 5 bends due to the temperature rise in the bulb 1, the amalgam metal 7 moves to a predetermined position, and the mercury vapor pressure can be controlled to be optimum even in a steady state. In addition, stem 3
Since the amalgam metal 7 is placed substantially at the center of the valve when the valve 1 is sealed, the amalgam does not get in the way, and the step of returning to a predetermined position after exhaust gas sealing is unnecessary. Is simplified.

[0015]

[Embodiment 2] FIG. 2 shows a different embodiment of the present invention. The difference from the above embodiment is that an alloy having a shape memorized at a predetermined temperature of the support 5, for example, iron-nickel is used. Since the other configurations are the same as those of the above-described embodiment by being made of a system shape memory alloy and having the amalgam metal 7 attached to the tip thereof, the description thereof will be omitted by giving the same reference numerals to the same configurations. Note that FIG. 2A shows a state at a low temperature, and FIG. 2B shows a state at a high temperature.

In this case, the support 5 includes the valve 1 and the stem 3.
2A is straight, as shown in FIG. 2A, the amalgam metal 7 is held at a position close to the center of the bulb 1, and the temperature rises when the lamp is lit after the lamp is manufactured. It is designed so that it bends as shown in b) and the amalgam metal 7 is located at a low temperature portion in the valve 1.

With this structure, the same effects as those of the above-described embodiment can be obtained in this embodiment.

[0018]

As described above, according to the present invention, the amalgam metal is disposed through the support whose shape is changed by the temperature change, and the shape change of the support is controlled by the amalgam metal being a valve when the lamp is off. It is arranged in the center, and when it is lit, it is arranged in the low temperature part inside the bulb, so that it is possible to improve the decrease in the amount of light immediately after lighting, and no auxiliary amalgam is required, that is, the discharge lamp that simplifies the manufacturing process. Can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention, in which (a) shows a state at a low temperature and (b) shows a state at a high temperature.

FIG. 2 is a cross-sectional view showing another embodiment of the present invention, (a)
Shows the state at low temperature, and (b) shows the state at high temperature.

[Explanation of symbols]

 1 Valve 2 Fluorescent Body 3 Stem 4 Support Tube 5 Support Body 6 Support Line 7 Amalgam Metal 8 Metal Mesh

Claims (1)

[Claims] 1. A discharge lamp in which at least mercury is enclosed in a translucent bulb and an amalgam metal for controlling the mercury vapor pressure is enclosed, and the shape of the amalgam metal is changed by a temperature change. It is arranged through the body, and the shape change of the support is such that the amalgam metal is arranged in the approximate center of the bulb when the lamp is off, and it is arranged in the low temperature part inside the bulb when the lamp is lit. And a discharge lamp.